Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef9abf4cd6ab7dea…

MALICIOUS

PDF

40.6 KB Created: 2020-09-18 23:12:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f3b2147cbf31ced8294e1a771f7277eb SHA-1: 7c80a1346ec149ffebb6f6db997c3e7d7619c48f SHA-256: ef9abf4cd6ab7dead2a50f2b78496752ba61ff6cf70a91003f4eb63d17a7e743
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a link that redirects to a known malicious infrastructure, likely to deliver a payload or phish for credentials. The document body, though heavily obfuscated, contains the URL and text related to 'force concept inventory test answers', suggesting a lure. The presence of numerous external PDF links also indicates a link farm, a common tactic for SEO poisoning or distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.club/wix?keyword=force+concept+inventory+test+answers
    • http://files.tindelltraining.com/uploads/1/3/1/4/131453214/xedoruwuxomukok-mijam.pdf
    • http://virad.nysfcja.org/uploads/1/3/0/7/130776394/budarojakixajutu.pdf
    • https://cdn.shopify.com/s/files/1/0437/0133/8280/files/lemolafobamufulo.pdf
    • https://cdn.shopify.com/s/files/1/0436/3531/0752/files/aptoide_older_version.pdf
    • https://cdn.shopify.com/s/files/1/0432/6565/4939/files/pimenajilov.pdf
    • https://4b15d451-3b84-4040-ae4e-4253431af1d8.filesusr.com/ugd/e32576_949530aa86d14a2f879aeb97fc770d6d.pdf?index=true
    • https://cdd6aa31-158e-446b-9125-991912cf48bf.filesusr.com/ugd/b58d21_9c2f9981edb545b48eeeff798ad5b2e6.pdf?index=true
    • https://f3c60321-1cc9-4acf-afbb-5574704b2317.filesusr.com/ugd/4cf28d_547b4ef2cc0b4f2492572563b89b3cc5.pdf?index=true
    • https://9471c1f7-a1c3-489b-96b2-99ae7d8aa5f6.filesusr.com/ugd/8e1900_b2e496ddc12749ca9d45f5211e6d6c70.pdf?index=true
    • https://4e3232b2-26d2-4b8e-b8c4-5defc0cc80d1.filesusr.com/ugd/0582e0_9da4980fe846496eb3aa43eb4d9e96ea.pdf?index=true
    • https://cdn.shopify.com/s/files/1/0430/3365/7498/files/98269284251.pdf
    • https://cdn.shopify.com/s/files/1/0436/0765/4563/files/bagowofam.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005b8e.bin
215c45ae77a8cd60cd27c5d33fc757aa6e3f7b800341a69e3864f6fe72d1c58c
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B8E 5104 bytes
font_01_sfnt_off00006d1b.bin
da4389bb75bbb3c29f1d38cf134b374679512e44752b9a6bf3b49d96929c1801
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D1B 12120 bytes